DO NOT REVIEW Plumb push messaging registration through to gcm.

content/public/browser/content_browser_client.cc

Index: content/public/browser/content_browser_client.cc
diff --git a/content/public/browser/content_browser_client.cc b/content/public/browser/content_browser_client.cc
index c669268c36a1f752c6b469dddd4e5f23e0850dc9..e01fffe2bdb30c15b022fbd01d8e3de68da7c385 100644
--- a/content/public/browser/content_browser_client.cc
+++ b/content/public/browser/content_browser_client.cc
@@ -241,6 +241,11 @@ SpeechRecognitionManagerDelegate*
   return NULL;
 }
 
+PushMessagingService* ContentBrowserClient::CreatePushMessagingService(
+    BrowserContext* browser_context) {
+  return NULL;
+}
+
 net::NetLog* ContentBrowserClient::GetNetLog() {
   return NULL;
 }